Tnx for your help, but I don't think that the problem is inside the gmail account, is one account like others and seems I'm the only one to have a problem with incredimail with gmail.

For me seems that the token for the authorization (like the OAuth2 for Thunderbird) have some problem. There's any way to completely remove incredimail, with registry track, all the files around the pc and try again?

In this case, you can try creating a new identity in IncrediMail and see if you are then able to configure the email account.

To create a new identity, please click on Tools > Identities > New Identity.

Set up the identity and see if you are then able to configure the Gmail account in IncrediMail.

Please note that I would like you to configure the same email address in your new identity, there is no need to create a new email address. While the identity name should be different, the email address should be exactly the same.

As everything is being done in the new identity, none of the data and settings in your original identity should be affected.

To switch back to your original identity, simply click on Tools > Switch Identity, select the appropriate identity, and click on OK.